The fury of Etna: Huge mushroom cloud dwarfs Sicily's famous volcano in one of the winning images of this year's Siena International Awards

An ominous ash cloud rising above the Etna volcano on Sicily, lighting strikes over a flock of cranes in Nebraska, and a storm developing into a supercell over Black Hawk, South Dakota, were some of the winners of the Siena International Photo Awards.

The mushroom cloud over the Italian volcano, entitled Etna in Eruption, was awarded a 'remarkable' by judges of the prestigious competition.

Another stunning snap shows a rare and jaw-dropping anti-cyclonic tornado touches down farmland, missing by little a house near Simla, Colorado, US.

Overall winner of Photographer of the Year 2017 was National Geographic photographer Randy Olson's snap of cranes in motion on the Ogallala Aquifer near Wood River, Nebraska, beating entrants from over 161 countries.

Mr Olson, who took the photo in August last year said: "There was a ton of lightning right behind the birds. I put the camera on a tripod and just started pumping the shutter, making sequential 30-second exposures. This shot happened to capture the lightning and all the birds in motion.'

Ominous: A cloud of ash rises in a mushroom shape over the Etna volcano on the Italian island of Sicily

Number one: Overall winner was National Geographic photographer Randy Olson's snap of cranes in motion on the Ogallala Aquifer near Wood River, Nebraska,

This photo, named Beast, shows a storm developing into a supercell over Black Hawk, South Dakota, US

This image of a frozen forest landscape by Eberhard Ehmke was also lauded by judges and given a 'remarkable award'

Stunning: A rare and jaw-dropping anti-cyclonic tornado touches down farmland, missing by little a house near Simla, Colorado, US

Beauty: This image by Miguel Angel Artus Illana was given an honourable mention by judges who praised his photo of a lighting strike in Tossa de Mar, Girona, Spain

This stunning photo was shot by Petar Sabol in Palovec, Croatia, when he spotted two dragonflies hiding under a flower as if it was an umbrella

Surprise: Italian photographer Filippo Borghi shot this sea lion cub who came out to play while he was diving in Mexico